Four new species of Muricidae are described from the Philippines and the Caribbean area. The first two (Homalocantha granpoderi n. sp. and H. ninae n. sp.), from the Philippines, are compared with four closely related species: H. scorpio (Linnaeus, 1758), H. pisori d’Attilio & Kosuge, 1989, H. vicdani d’Attilio & Kosuge, 1989 and H. dondani d’Attilio & Kosuge, 1989. The need for comparisons based on an ontogenetic growth series is underlined for these species. For the first time, the growth series of each discussed species is illustrated. Siratus pointieri n. sp., from the Dominican Republic, is compared with three closely related species: S. cailleti (Petit de la Saussaye, 1856), S. motacilla (Gmelin, 1791) and S. kugleri (Clench & Pérez Farfante, 1945). Murexsul (M.) jahami n. sp., from Martinique, is compared with M. (M.) sunderlandi (Petuch, 1987), M. (M.) oxytatus (Smith, 1938), M. (M.) zylmanae (Petuch, 1993) and M. (M.) chesleri Houart, 2006. The characters of the spiral sculpture are described using precise structural homologies for each species.
Mollusca, Gastropoda, Muricidae, Homalocantha, Siratus, Murexsul, Philippines, Caribbean, new species.